According to a story from Pulmonary Arterial Hypertension News, data from an open label extension trial of the drug Orenitram as a treatment for pulmonary arterial hypertension has demonstrated that the drug can deliver a dose dependent improvement in exercise capacity, providing benefits that the researchers have deemed “moderate” yet durable. The findings from this trial were first released in the scientific journal Pulmonary Circulation.
About Pulmonary Arterial Hypertension (PAH)
Pulmonary arterial hypertension is a condition in which the blood pressure in the arteries of the lungs is abnormally high. The cause of pulmonary arterial hypertension is often unknown in many cases. However, there are a variety of potential causes, such as certain heritable genetic mutations, exposure to certain toxins, and drug use (ex. methamphetamine). It can also appear as a symptom or complication in a number of other diseases, such as heart disease, connective tissue disease, and infection with HIV. The arteries in the lungs are often inflamed. Symptoms of this condition include rapid heartbeat, poor exercise tolerance, shortness of breath, fainting, leg swelling, fatigue, and chest pain. Treatment may include a number of medications and surgical operations, including lung transplant. A transplant can cure the condition, but it can cause many complications. Survival rate is often only about two or three years without treatment, but the latest drugs can prolong life by several years or more. Click here to learn more about pulmonary arterial hypertension.
Orenitram is developed as an orally available formulation of the drug treprostinil, which was previously only available in an injectable form. Unfortunately, intravenous and subcutaneously administered drugs have been found to have significant side effects such as blood clots, pain at the injection site, and even infection of the blood. Orenitram is designed to circumvent these problems.
Orenitram has been approved as a therapy for pulmonary arterial hypertension for years, but this study was designed with the intent to investigate the long term benefits of the treatment using a large patient sample. The study included a total of 894 patients. With a mean age of 48 years, these patients had all participated in Orenitram clinical trials when it was still being developed.
Following at least a year of use, 569 patients saw their their distance in the six minute walk test increase by a median distance of 22 meters (72 feet). Patients with low doses saw the smallest degree of improvement and those with the highest doses saw the greatest degree. The scientists concluded that the longer term use of the drug could result in minor but sustained improvements in exercise capacity for pulmonary arterial hypertension patients.
Check out the original study here.